True positional 3-D audio has long been an elusive dream of Mac gamers. While almost all gaming PCs can separate left, right, rear, and center audio channels, only the G5 offers this ability on the Mac. But now that’s changing, thanks to M-Audio’s Revolution 5.1—a new audio card that lets your Mac output 5.1 surround sound.

Although the card is being marketed primarily to gamers, its benefits range beyond the gaming world. You can use the card to watch DVDs in surround sound with Panther’s DVD Player, for example, or use it to record 5.1 audio.

But the card really shines in first-person shooters and other action games where 3-D audio cues can tell you when a bad guy is just around the corner or let you know from which direction you’re being strafed. This can mean the difference between getting fragged and winning a round.

Currently, few games on the Mac take advantage of 5.1 audio. But thanks to OpenAL, an open technology standard that’s gaining traction with PC and Mac game developers, more Mac games will be able to output positional 3-D audio to this card in the future. In fact, the card even comes with one such game—a modified version of Aspyr’s Wakeboarding Unleashed Featuring Shaun Murray.

Setting up the card is simple—just insert it into any available PCI slot on a 733MHz G4 or better. Even G5 Power Macs, which already offer 5.1 output, can benefit from the Revolution, since it takes the burden of processing away from the Mac’s CPU. The game technically supports both OS 9 and OS X systems. However, no OS 9 games currently support multichannel sound—or are likely to in the future—nor does the OS 9 version of Apple’s DVD player. So the benefits to OS 9 users are limited.

Across the card’s backplane are a series of 1⁄8-inch jacks for connecting an analog audio source such as a CD player, a microphone, a set of headphones, an amplified 5.1 surround speaker system, and a digital coaxial connector.

The OS X application that powers the card provides extensive control over how your audio sounds. You can set parameters for how your surround system is set up, turn off individual channels, and even apply digital surround effects to audio sources that aren’t in true 3-D.

I’ve read reports of stability problems with this card. Some gamers have reported kernel panics and other issues after installing the card. However, I didn’t have any of those problems in my 1GHz dual-processor G4.

The Bottom Line
At $100, the Revolution 5.1 costs a lot more than PC gamers are used to paying for the privilege of having surround sound (although you can pick up the card online for considerably less). But for Mac gamers, 5.1 sound is a novelty—hopefully one that will continue to grow in popularity. l